JPH04359822A - Vacuum valve - Google Patents

Abstract

PURPOSE:To obtain a vacuum valve with a simple structure and excellent mechanical properties and electrical properties as well. CONSTITUTION:In the case of joining a main electrode 8 and a coil electrode 9 to be connected with the back side of the main electrode through an electric connection part 9d, a metal coating of such as Cu or Ni, which is able to be soldered through an electrically insulating ceramic coating, is formed on at least one of the surface of the coil electrode 9 except the electric connection part 9d in the main electrode side and the surface of the main electrode 8 in the coil electrode side and joined each other.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum valve with excellent mechanical and electrical performance.

0002

2. Description of the Related Art Vertical magnetic field electrodes that generate a magnetic field parallel to the arc when interrupted have already been put into practical use, and a typical configuration thereof is shown in FIG. The electrode 1 includes a main electrode 2, a coil electrode 3 provided on the back surface of the main electrode 2, and a reinforcing member 4 provided between the main electrode 2 and the coil electrode 3. Here, the coil electrode 3 includes a center part 3a fixed to the current-carrying shaft 5, an arm part 3b extending from the center part 3a toward the outer periphery, and an arc-shaped arm part 3b extending concentrically with the current-carrying shaft 5 from the tip of the arm part 3b to conduct current. A circular arc shape 3c forming a path and a connecting protrusion 3d electrically connected to the main electrode are provided, and a magnetic field parallel to the arc is created between the opposing electrodes by the current flowing in the circumferential direction through each circular arc portion 3c. This stabilizes the vacuum arc that occurs between the electrodes, making it possible to interrupt large currents.

0003

However, in the structure of the electrode 1 described above, the current path passes from the current-carrying shaft 5 to the main electrode through the central part 3a of the coil electrode, the arm part 3b, the circular arc part 3c, and the connecting protrusion 3d. This is the route that leads to 2. Here, the center part 3a- of the coil electrode is arranged so that the current flows through the circular arc part 3c.
A gap d is provided between the arm portion 3b-arc portion 3c and the main electrode 2 for electrical insulation, and a reinforcing member 4 is provided to prevent deformation even if a compressive or tensile force is applied to the electrode. It is arranged. Here, the gap d needs to be large enough to prevent the coil electrode 3 and the main electrode 2 from coming into contact even if they are deformed by the force acting on the electrodes. For example, if the electrode diameter is about 100 mm, the gap d is 2.
~5mm is required. In this case, the arc portion 3 of the coil electrode
The distance from the central axis of c to the midpoint between opposing electrodes is 1
It is around 5mm. Since the magnitude of the magnetic field generated by a current is inversely proportional to the square of the distance from the current, the gap d(
For example, 2 mm), the strength of the magnetic field generated between the electrodes is approximately 30% ((15/13)2 -1) x 1
00% = 33%), the stability of the vacuum arc generated between the electrodes is reduced, and the large current interrupting performance is reduced. Furthermore, in order to provide this gap, it is necessary to provide the coil electrode 3 with a connecting protrusion 3d, resulting in a complicated shape and an increase in price. On the other hand, coil electrode 3
Since the electrode is made of a material with low rigidity such as oxygen-free copper, it is necessary to provide and connect a reinforcing member 4 to prevent deformation of the electrode. Even when reinforced with this reinforcing member 4, there was still a drawback that the coil electrode 3 and main electrode 2 were deformed by the impact when the electrode was inserted or opened. Furthermore, a reinforcing member 4 is installed.
By joining, a part of the current that should flow through the arc portion 3c of the coil electrode 3 is shunted through the reinforcing member 4, weakening the strength of the magnetic field, which also has the disadvantage of reducing large current interrupting performance. . An object of the present invention is to provide a vacuum valve that is mechanically strong and has excellent large current interrupting performance. [Structure of the invention]

0004

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a pair of main electrodes that can be moved in and out of the vacuum container, and an electrical connection part is provided on the back surface of at least one of the main electrodes. In a vacuum valve equipped with a coil electrode that generates a longitudinal magnetic field and connected through the electrical connection portion, at least one of the main electrode side surface of the coil electrode or the coil electrode side surface of the main electrode other than the electrical connection portion is provided with an insulating material interposed therebetween. The main electrode and the coil electrode are joined by forming a metal film that can be brazed.

[0005] Furthermore, a pair of main electrodes that can be moved into and out of contact with each other are disposed in the vacuum container, and a coil electrode that generates a longitudinal magnetic field is connected to the back surface of at least one of the main electrodes through an electrical connection part, These coil electrodes include a first coil electrode, one end of which is connected to the main electrode, and a second coil electrode, which is connected to the other end of the first coil electrode and generates a longitudinal magnetic field in the same direction as the first coil electrode. In the vacuum valve, brazing is possible via an insulating material on one surface between the main electrode and the first coil electrode other than the connection part and on one surface between the first coil electrode and the second coil electrode. They are bonded together by forming a metal film.

[0006]

[Operation] In this configuration, the main electrode and the coil electrode are connected through an insulating material except for the electrical connection part, so that the current that generates a magnetic field parallel to the interrupting arc flowing through the coil electrode is A magnetic field parallel to the arc of effective strength is generated between the electrodes without damage, and the main electrode and coil electrode are connected across the entire surface with insulating material, resulting in improved mechanical and electrical performance.

[0007]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of an electrode portion of a vacuum valve showing an embodiment of the present invention, and FIG. 2 is a partial sectional view of a coil electrode.

In FIGS. 1 and 2, 8 is a main electrode, 9 is a coil electrode, and 5 is a current-carrying shaft. Here, the coil electrode 9 has a center part 9a fixed to the current-carrying shaft 5, an arm part 9b extending from the center part 9a toward the outer periphery, and an arc-shaped arm part 9b extending concentrically with the current-carrying shaft 5 from the tip thereof to carry a current. It consists of a circular arc portion 9c that forms a path and an electrical connection portion 9d that electrically connects to the main electrode. In FIG. 2, which shows a part of a vertical cross-sectional view of the coil electrode 9, a ceramic film, which is an electrical insulator, is coated with a thickness of 0.1 to 0.5 mm on the surface of the coil electrode 9 on the main electrode 8 side, excluding the electrical connection portion 9d. A metal film made of Cu or Ni is formed on the surface of this ceramic film. That is, the coil electrode 9 and the main electrode 8 are electrically connected at the electrical connection portion 9d of the coil electrode 9, and are bonded to each other via the ceramic film at other portions. With this configuration, the coil electrode 9 and the main electrode 8 can be joined to each other over a wide area without providing a gap, so that a stronger longitudinal magnetic field can be obtained. on the other hand,
Since the coil electrode 9 is connected to the main electrode 8 through the ceramic film 10 except for the electrical connection part 9d, the resistance between the coil electrode 9 and the main electrode 8 except for the electrical connection part 9d is very small. Large (thickness of ceramic film is 0.1~
Even if it is as thin as 0.5 mm, it is considered to be practically electrically insulated). Therefore, the current flowing through the coil electrode 9 is
Since the current flows entirely through the circular arc portion 9c without branching to the main electrode 8 on the way, a sufficient magnetic field parallel to the interrupting arc can be obtained. Therefore, the stability of the vacuum arc generated between the electrodes is improved, and the large current interrupting performance is improved. Further, since it is no longer necessary to provide a gap d between the coil electrode 9 and the main electrode 8, the shape of the coil electrode 9 can be simply processed, and processing costs can be reduced. Furthermore, since the main electrode 8 and the coil electrode 9 can be directly joined, there is no need to provide a reinforcing member 4 as in the conventional case. Furthermore, since the main electrode 8 and the coil electrode 9 are joined over the entire surface, deformation of the main electrode 8 and the coil electrode 9 due to impact when the electrode is inserted or opened is reduced.

[0009] The present invention is not limited to the above embodiments, but
For example, the shapes of the coil electrode 9 and the main electrode 8 can be modified in various ways. Further, the shape of the coil electrode does not necessarily have to be flat, but may be any shape that engages with the main electrode.

In FIG. 3 showing another embodiment, the electrode section includes a main electrode 8, a coil electrode 9 provided on the back surface thereof and connected to the current-carrying shaft 5, and a coil electrode 9 connected to the main electrode 2.
It is composed of. Here, the coil electrodes 9 and 9' have surfaces facing each other excluding the respective electrical connection parts 9d and 9'd, and the coil electrode 9 has the main surface excluding the connection surface between the center part 9a and the main electrode 2. Ceramic film, which is an electrical insulator, is 0.1 to 0.5 mm thick on the surface facing the electrode.
Cu is formed on the surface of this ceramic film to a thickness of
Alternatively, a metal film made of Ni is formed. This produces similar effects.

[0011]

Effects of the Invention As described above, the present invention provides a main electrode and a coil electrode that is connected to the back surface of the main electrode via an electrical connection part. Since a brazingable metal film is formed and bonded to at least one of the coil electrode side surfaces of the electrode via an insulating material, a vacuum valve with excellent mechanical performance and electrical performance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of the electrode section of the vacuum valve of the present invention.

FIG. 2 is a partial cross-sectional view of the coil electrode in FIG. 1.

FIG. 3 is an exploded perspective view of an electrode section of a vacuum valve showing another embodiment of the present invention.

FIG. 4 is an exploded perspective view of the electrical part of a conventional vacuum valve.

[Explanation of symbols]

8... Main electrode, 9... Coil electrode, 9a... Center part, 9
c...Circular arc part, 9d...Electrical connection part.

Claims (2)

[Claims] Claim 1: A pair of main electrodes that can be moved into and out of contact with each other are disposed in a vacuum container, and a coil electrode that generates a vertical magnetic field is connected to the back surface of at least one of the main electrodes through an electrical connection. In the vacuum valve, a metal film that can be brazed to the main electrode is formed on at least one of the main electrode side surface of the coil electrode other than the electrical connection part or the coil electrode side surface of the main electrode through an insulating material. A vacuum valve characterized by joining a coil electrode. 2. A pair of main electrodes that can be moved into and out of contact with each other are arranged in a vacuum container, and a coil electrode that generates a vertical magnetic field is connected to the back surface of at least one of the main electrodes through an electrical connection part, These coil electrodes include a first coil electrode, one end of which is connected to the main electrode, and a second coil electrode, which is connected to the other end of the first coil electrode and generates a longitudinal magnetic field in the same direction as the first coil electrode. In the vacuum valve, brazing is possible via an insulating material on one surface between the main electrode and the first coil electrode other than the connection part and on one surface between the first coil electrode and the second coil electrode. A vacuum valve characterized by forming metal films and bonding them together.